Process of agglomerating ore and the like



April 7, 1925. 1,532,113

N. AHLMANN I PROCESS OF AGGLOMERATING ORE AND THE LIKE Filed Oct 20. 1922 r 2 Sheets-Sheet 1 INVENTOR whoa WW April 7, 1925. I 1 1,532,113

' N. AHLMANN PROCESS OF AGGLOMERATING ORE AND THE LIKE- Filed Oct. 20. 1922 2 Sheets-Sheet 2 INVENTOR QMLQZZMM 6 :2: ATTORNEYS v Patented Apr. 7, 1925.

NIKOLAI AHLMANN, 0F

COPENHAGEN, DENMARK.

PROCESS OF AGGLOMERATING ORE AND THE LIKE.

Application filed October 20, 1922. Serial No. 595,858.

To all whom it may concern:

Be it known that I, NIKOLAI AHLMANN, a subject of the King of Denmark, residing at 22 F. Hrsholmsgade, Copenhagen, Denmark, have invented certainnew and useful Improvements in Processes of Agglomer- 'ating Ore and the like, of which the following is a specification.

In the agglomeration of pulverous ore in rotary kilnit is as a rule necessary, in order to obtain an agglomerate'with a small proportion of dust, to heat the ore to such a high degree that sintering, i. e. a partial melting of the material, takes place in the the grains of the ore can kiln. The resulting agglomerate willthen consist of lumps, or so-called nodules, which are often of suflicient mechanical strength and at the same time somewhat porous, but do not possess the high degree of porosity which is required for the subsequent treatment of the nodules in blast furnaces. On the other hand, a high degree of porosity can be attained at the sacrifice of the mechanical strength by briquetting the pulverous ore in a cold state and burning the resulting briquettes at such low temperature that no sintering will be created.

It is, however, known that for the melting of the ore in blast furnaces the nodules should combine a high degree of porosity with-great mechanical strength, and-it is the purpose of the present invention to attain this result.

'The invention is based upon the discovery that at a temperature materially lower than the sintering temperature the pulverous ore will be of such consistency that by pressure be made to stick strongly together while at the same time the mass 0t material will have a very high porosity. L

In accordance with the invention, therefore,'the pulverous ore is heated in a rotary kiln to the temperature required which, as it will be understood, is lower than the sintering temperature for the ore, and then,

in a suitable machine, eitherinto briquettes or into other suitable form.

In the accompanying drawing- Figure 1 is a partial view, in vertical sec tion and in outline, of apparatus in'which the invention can" be practiced.

Figure 2 is a glanview in outline of the press shown in igure 1.

while it has still this temperature, is pressed,

Figure 3 is a view similar to Figure 1 but showing a different form of press.

- The particular design of apparatus employed in the practice of the invention is unimportant, but it should be constructed with due regard to the fact that it has to treat glowing material. In Figures 1 and -2 of the drawing is illustrated somewhat diagrammatically a form of apparatus adapted for the practice of the invention,

comprlsing a rotary kiln a with a hood I) and a suitable fuel nozzle 0 by which the flame is directed as usual into the kiln.

From the kiln the hot material may fall into a hopper d from which it is delivered to a rotating table 6 which is provided with molds f lined with fire brick 9. As the table 6, supported upon a suitable base h, is rotated with a step by step motion the heated material in each mold, at a point opposite the hopper d, is subjected to, the ressure of a suitable. plunger 11 and the br1quette thus formed is discharged in the further movement of the press table e, through an opening provided at k in the base It.

In the form of apparatus shown in Figure 3 the kiln a, hood 12, fuel nozzle 0 and hopper d are arranged substantially as shownin Figure 1. From the hopper d the heated material is delivered into awater cooled cylinder Z and is there subjected to pressure between two pistons m, n, the piston'm being then withdrawn to permit the discharge of the briquette by the continued forward movement of the piston n.

'Other forms of apparatus in invention can be practiced will suggest themselves. It will be obvious, for example, that the heating of the pulverous ore to the temerature suitable for the briquettingJ might e efiected by the rapid oxidation rought about by forcing a currentpf air or of a mixture of air and water yapor through the pulverous ore-which has been heated and more or less reducedin the kiln.

I claim as my invention:

The process of agglomerating ore which consists in heating the pulverous material to a temperature less than'the sintering temperature and then sub'ecting the heated material to pressure to orm a coherent, porous mass.

This specification signed this 5th day of October, A. D. 1922. 1

NIKOLAI AHLMAN N.

9d which the *pulverous 

